In a photolithography process in a manufacturing process of a semiconductor device, for example, a resist coating treatment of applying a resist solution onto a wafer to form a resist film, exposure processing of exposing the resist film to a predetermined pattern, a developing treatment of developing the exposed resist film and so on are performed in sequence to form a predetermined resist pattern on the wafer.
In the above-described resist coating treatment, a so-called spin coating method is widely used in which a resist solution is applied over a front surface of a wafer by supplying a resist solution from a nozzle to a central portion of the wafer rotated at a high speed and diffusing the resist solution on the wafer by centrifugal force. Further, in this spin coating method, as a method of applying the resist solution more uniformly, a method has been proposed in which, for example, after the supply of the resist solution to the wafer rotated at a high speed is finished, the rotation of the wafer is once decreased to flatten the resist solution on the wafer, and the rotation of the wafer is then increased again to dry the resist solution on the wafer (see Patent Document 1).